The Satellite Snow Product Intercomparison and Evaluation Experiment Objectives, Status, Expected Results

Transcription

1 SnowPEx Satellite Snow Product Intercomparison and Evaluation Experiment (6/2014 5/2016) The Satellite Snow Product Intercomparison and Evaluation Experiment Objectives, Status, Expected Results Thomas Nagler ENVEO

2 (Derksen & Brown 2012) Trend of June (minimum) NH Snow Extent From snow cover from NOAA snow chart CDR derived Rate of June-SE : -21.5% / decade

3 Spatial Difference of Snow Products (versus maximum snow extent) JASMES MDS10C Binary, 5 km March 2008 MOD10_C5 Fractional, 0.5 km

4 SnowPEx Objectives The primary objectives are Intercompare and evaluate global / hemispheric (pre) operational snow products derived from different EO sensors and generated by means of different algorithms, assessing the product quality by objective means. Evaluate and intercompare temporal trends of seasonal snow parameters from various EO based products in order to achieve well-founded uncertainty estimates for climate change monitoring. Elaborate recommendations and needs for further improvements in monitoring seasonal snow parameters from EO data. The project will support the setup of a consolidated operational satellite snow observation system for the Global Cryosphere Watch Initiative of the WMO and help to improve the snow cover data base for climate monitoring, as addressed by the WCRP-CliC programme.

5 Main Tasks within SnowPEx Review of Algorithms and products focusing on Snow Extent (SE) and Snow Water Equivalent (SWE) Definition of protocols and methods for validation and intercomparison of SE / SWE products Definition and compilation of reference data sets for quality assessment of SE and SWE products Intercomparison of SE / SWE products from various institutions and the quality assessment against reference data base Analysis of Hemispheric/Global SE and Snow Mass Trends and its uncertainty Study the synergy of SE and SWE products Conclusion and recommendations for satellite snow monitoring and publication of project results

6 Study Logic - Status Review of SE / SWE Algorithms and Products Identification of reference data ISSPI WS-1 July 2014 Methods and Protocols for Validation & Intercomparison of SE / SWE Products P R O G R E S S Compilation of Reference Data Set Validation and Intercomparison of Products (1st results) ISSPI WS-2 Sep 2015 Trend Analysis of SE / SWE products (1st results) Validation and Intercomparison of Products (Final Results) Trend Analysis (Final) SE & SWE Synergy Products Publication of Project Results, Conclusions, Recommendations for satellite snow monitoring

7 Organisations Providing Snow Products to SnowPEx

8 SnowPEx Snow Extent Products SnowPEx PROD. ID Product Name Thematic Parameter Frequency Period Pixel Sp. Contact ASNOW Autosnow Binary, Global daily 2006 present 4 km P. Romanov / NESDIS CRCLIM CryoClim Binary, Global daily 1982 present 5km R. Solberg / NR CRYOL CryoLand Fractional, PanEU daily 2000 present 0.5 km T. Nagler / ENVEO EURAC EURACSnow Binary, Alps daily 2002 present 0.25 km C. Notarnicola / EURAC GLSSE GlobSnow v2.1 Fractional, NH daily - monthly km S. Metsämäki / SYKE HSAF10 HSAF H10 Binary, PanEU daily 2009 present 5 km M. Takala / FMI IMS01 IMS Binary, NH daily 2014 present 1 km S. Helfrich / NOAA IMS04 NOAA IMS Binary, NH daily 2004 present 4 km S. Helfrich / NOAA IMS24 NOAA IMS Binary, NH daily km S. Helfrich / NOAA JXAM5 JASMES GHRM5C Binary, Global daily, weekly half-monthly km M. Hori / JAXA JXM10 JASMES MDS10C Binary, Global daily, weekly half-monthly km M. Hori / JAXA M10C05 MOD10_C5 Fractional, Global daily 2000 present 0.5 km D. Hall, G. Riggs / NASA MEASU MEaSUREs Binary, Global daily km D. Hall / NASA D. Robinson / U. Rudgers PATHF AVHRR Pathfinder Fractional, NH daily km R. Fernandes / NRCAN SCAG SCAG Fractional, NH daily km T. Painter / NASA

9 MEaSUREs JASMES MDS10C CC, PN JASMES GHRM5C CC, PN AVHRR Pathfinder CryoClim NOAA IMS AutoSnow GlobSnow, CC, PN MOD10_C5 CC, PN SCAG, CC, PN? CC cloud cover PN polar night

10 SnowPEx SE Status Update SE Products data base 15 participating and independent products of 5 years digitally recoded according to SnowPEx specs and database made available at snowpex.enveo.at Reprojecting SE Products to common EASE Grid 2 Projection presentation by G. Bippus et al. Methods for re-gridding of SE products implemented and uncertainty evaluated Transformation of all products to EASE GRID 2 with 5 and 25 km pixel spacing completed SE product intercomparison of independent gridded data sets: Protocol by CCRS implemented and first results -> pres. by R. Fernandes Protocol by ENVEO implemented and first results -> pres. by G. Bippus Completion of Intercomparison of all products and years Ideas for summarizing and reporting of intercomparson results will be presented and further discussed at splinter sessions

11 SnowPEx SE Status Update In situ reference datasets presentation by S. Metsämäki et al. Dataset in various regions compiled, distribution partly restricted, but available upon request Methods for validation with insitu data implemented and first results complete validation of full dataset Consolidation of method and presentation of validation results in splinter session Landsat Reference datasets presentation by Elisabeth Ripper et al. HR Snowmaps from Landsat (459 scenes) in different environments using 4 algorithms (2 fractional, 2 binary) generated and aggregation to resolution of Hemis/Global Products completed First results generated Discussion on validation results in splinter session Trend analysis First results available Will be discussed in splinter session

12 SnowPEx SWE Datasets Dataset Method Ancillary/ Forcing Data GlobSnow NASA AMSR-E standard NASA AMSR-E prototype ERAint-Land MERRA Crocus GLDAS-2 Passive microwave + in situ Standalone passive microwave Microwave + ground station climatology HTESSEL land surface model Catchment land surface model ISBA land surface + Crocus snow model Noah 3.3 land surface model Weather station snow depth measurements Resolution Time Series Reference 25 km Takala et al (2011) none 25 km Kelly (2009) Weather station snow depth climatology 25 km TBD ERA-interim 0.75 x Balsamo et al (2013) MERRA 0.5 x Rienecker et al (2011) ERA-interim 1 x Brun et al (2013) Princeton Met. 1 x Rodell et al (2004)

13 SnowPEx SWE Status Update Product acquisition and pre-processing: Participating SnowPEx and independent gridded SWE products in place Reference datasets: Acquired; distribution generally restricted, but available upon request Gridded dataset inter-comparison: Completed (presentation by L. Mudryk et al.; J. Climate paper) Comparison with in situ reference datasets (SYKE; FMI; RusHydroMet): comparison with SnowPEx products completed (present. by K. Luojus et al.) comparison with independent gridded SWE products planned Comparison with in situ reference datasets (North American; SLF): comparison with SnowPEx and independent gridded products underway (pres. by R. Brown et al.) Watershed analysis in progress (presentation. by C. Vuyovich et al.) Trend analysis in progress (presentation by L. Mudryk et al.)

14 Anomaly Correlation

15 Objectives of ISSPI WS-2 Review of reference data sets for snow product validation including in-situ data and reference snow products from high resolution optical satellite data Presentation and discussion of intercomparison and validation of snow products and elaboration of required refinements for the protocols and guidelines. Present initial temporal trends of seasonal snow cover and discuss potential further analysis with SnowPEx data sets Discuss potential synergistic use of snow products from optical (snow extent) and passive microwave (SWE) data

16 ISSPI WS-2 AGENDA MONDAY, 21 July 2014 Mon-1 09:00 09:50 Opening and Overview Thomas Nagler / Chris Derksen Mon-2 09:50 10:30 Snow Extent Products 1 SnowPEx Protocols & results Thomas Nagler / Chris Derksen Mon-3 11:00 12:40 Snow Extent Products 2 Ref. Data, Product Updates Richard Fernandes / David Robinson Mon-4 14:00 15:40 Snow Extent Product 3 - Product Updates George Riggs / Rune Solberg Mon-5 16:10 17:00 Poster Presentations Gabriele Bippus / Karl Rittger 17:00 19:00 Ice Breaker and Poster Session TUESDAY, 22 July 2014 Tue-1 09:00 10:40 Snow Water Equivalent 1 Chris Derksen / Carrie Vuyovich Tue-2 11:10 12:30 Snow Water Equivalent 2 Kari Luojus / Lawrence Mudryk Tue-3 14:00 15:30 Tue-4 16:00 17:30 Splinter Session -1 SE / Reference DS, Protocols, SWE / Results, validation with in-situ Splinter Session -2 SE / Results, Trends analysis SWE / Trends analysis Non hostet Dinner WEDNESDAY, 23 July 2014 Wed-1 9:00 9:40 The role of product intercomparison in the GCW Jeff Key Wed-1 9:40 11:00 Wed-2 11:30 13:00 Splinter Session-3 SE SWE Summary of Splinter Sessions SE & SWE Discussion and Next Steps Wed-3 13:00 Closing of Workshop Thomas Nagler / Richard Fernandes Chris Derksen / Kari Luojus Thomas Nagler / Richard Fernandes Chris Derksen / Kari Luojus Thomas Nagler / Richard Fernandes Chris Derksen / Kari Luojus Splinter Chairs & Rapporteurs Thomas Nagler, Chris Derksen, Bojan Bojkov,

17 Expected Outcome of ISSPI WS-2 DATE: September 2015 VENUE: NSIDC / Boulder The expected outcome of the International Snow Product Intercomparison Workshop 2 o Agreed protocols and procedures for validating and intercomparing of snow products o Agreed data sets for validation and data sets o Agreed approach for analysing temporal trends using SnowPEx products data sets o Agreed framework for reporting results on SnowpEX website, in peer reviewed journal (joint publication) and conferences.

18 Questions? Please your question to Subject: SnowPEx Questions will be addressed in the splinter session